Something violently supernatural had happened, something strong enough to leave an imprint on the corpse of part-time jazz saxophonist Cyrus Wilkinson as if he were a wax cylinder recording. He’s not the first musician to drop dead of a heart attack right after a gig, but no one was going to let me start examining corpses to check for supernatural similarities. Instead, it was back to old-fashioned police legwork. It didn’t take me long to realise there were monsters stalking Soho, creatures feeding off the gift that separates great musicians from those who can raise a decent tune. What they take is beauty. What they left behind is broken lives.

And as I hunted them, my investigation got tangled up in another story: a brilliant trumpet player, Richard ‘Lord’ Grant – my father – who managed to destroy his own career. Twice.

Policing: most of the time you’re doing it to maintain public order. Occasionally you’re doing it for justice. And, maybe once in a career, you’re doing it for revenge.

There’s a longer plot in these books. What happened in the end of the first, is picked right up again in the beginning of the second and the characters… well, they stay true to themselves and the changes they’ve had to gone through. Some lessons take longer to learn than the others.

Like in Rivers of London there’s two plot threads advancing simultaneously in this book. There’s the long plot about Peter growing as a magical apprentice and then there’s the short plot and an incidental murder that needs solving. At this point you’re either reading the book for the characters or the mystery, and let’s just say that I can’t remember anything about the short plot.

Like all good show runners know, there needs to be a big bad that the hero has to strive to defeat. Make it impossible and there’s no point for the series, but make it too easy and it’s boring. Aaronovitch went with the limited exposure and only gave the frayed end of a very thin thread for Peter and his master to follow. Unlike the YA authors, the young apprentice hero isn’t expected to save the world all on his own a couple of months after he’s learned his first spell. He has help, which in Peter’s case means the Metropolitan Police and Nightingale. The adults supervise the younglings.